On Weak Condorcet Winners: Existence and Uniqueness

Ayllon Aragon, Grisel (2013): On Weak Condorcet Winners: Existence and Uniqueness. Published in: PERSPECTIVAS: Revista de análisis de Economía, Comercio y Negocios Internacionales , Vol. 7, No. 1 (January 2013): pp. 3-14.

Abstract

Consider a society where each agent has weak preferences over alternatives. The purpose of the society is the selection of alternatives using the majority principle. Then, an alternative x (a weak Condorcet winner) is selected if half or more agents agree that x is as least as good as any other alternative. We give necessary and sufficient conditions on preference profiles under which (i) the set of Weak Condorcet Winners is non-empty; and (ii) the Weak Condorcet Winner is unique.

• Item Type: MPRA Paper
• Language: English
• Keywords: Condorcet Winner, Majority Principle
• Subjects: D - Microeconomics > D7 - Analysis of Collective Decision-Making > D70 - General; D - Microeconomics > D7 - Analysis of Collective Decision-Making > D71 - Social Choice ; Clubs ; Committees ; Associations

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